The overall objective is to develop an effective regimen of Desferrioxamine (DF) therapy which can lead to an extension of life in thalassemia patients. Animal studies will examine the feasibility of using a totally implantable, constant rate infusion pump for the chronic administration of DF. Data will be obtained concerning the pharmacology and chronic toxicity of DF when administered in such a fashion. We will also determine the ability of chronic DF therapy to prevent the biochemical changes associated with hypertransfusion in the rat, namely glutathione oxidation and conjugated diene formation. Furthermore, in an effort to develop a long-acting DF preparation, derivatives of DF will be synthesized and evaluated in a rat model of secondary hemosiderosis. Clinical studies will determine the optimal dosage regimen of continual intravenous DF and the age at which such a regimen is effective. The effect of an intensive regimen of intravenous and intramuscular DF on cardiac and endocrine function in patients with thalassemia major will be thoroughly evaluated.